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  <script>
    var message = "hello world"
    var message = "你好,世界"

    let address = "广州市"
    // let address = "广州市" //Uncaught SyntaxError: Identifier 'address' has already been declared

    const info = {}
    // const info = {} // Uncaught SyntaxError: Identifier 'info' has already been declared


  </script>
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